including a gridded version. The coordinate system does not match the old one derived from Hubble images, a point that is causing some controversy, but I have little doubt that this will become the official coordinate system eventually. Another image in the new set defines the prime meridian marker:

It's amazing how there are some very distorted ancient basins in the more tropical latitudes. And perhaps another giant basin that creates a gap in the south polar crater "rim." And the grooves aren't equidistant from the center of the southern crater, are they?

It's amazing how there are some very distorted ancient basins in the more tropical latitudes. And perhaps another giant basin that creates a gap in the south polar crater "rim." And the grooves aren't equidistant from the center of the southern crater, are they?

Sharp eyes you have there! we have been discussing both aspects (ancient degraded craters, and the large "Giant basin" as you call it, for several weeks. Vesta definitely has a history predating the large south polar basin.

False color map of Vesta - very nice! It's not the full range of longitudes, only about 240 degrees long, and it doesn't register exactly with the recent base map (different projection), but it is interesting. This barely gets into the south polar depression at its southern edge.

It's clearly a basin. The trick is, what caused it? That wonderful south polar impact threw up a huge amount of ejecta, a fair portion of which would have fallen back to the surface in all sorts of interesting ways. Shaking from the impact doubtless created some interesting structures. Based on what we know so far, Vesta's going to be a tough (and tasty!) nut to crack.

I had an interesting and very pleasant communication with Dr. Marc Rayman; he explained me that, until few hours ago, Vesta distance reported in the Simulator was based on extrapolated values of distance from asteroid centre, not height. I corrected my database and now is clear that Dawn is very close to HAMO final orbit, both in terms of height and speed (685 km and 135 m/s):

update: in the bottom/left plot I changed potential energy (now represented with the correct negative sign) and I added total energy curve (kinetic+potential).

Yes! It's very interesting to overlay the Hubble compositional maps (in Li et al., Icarus 208 (2010) 238–251, for instance) over the new maps. Even quite small crater ejecta deposits line up very well. The two 'red' patches (false color) were clearly seen, but mapped as different things (Eucrite and weathered materials). No doubt we'll be getting team publications on this in due course.

In Universe Today is an interview with Prof. Chris Russell and Carol Raymond.

South pole impact feature has been officially named Rhea Silvia after the mother of Romulus and Remus, mthyical mother of the Vestal virgins.

Prof. Chris Russell“We have set ourselves a target to gather everything we know about the south pole impact feature and expect to have a press release from what ever we conclude at the GSA (Geological Society of America) meeting on October 12. “We will tell the public what the options are.

“We do not have a good analog to Vesta anywhere else in the Solar System and we’ll be studying it very intently.”

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted.
Do not reproduce without permission. Read
here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the
individual posters and do not necessarily reflect the opinions
of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer
UnmannedSpaceflight.com moderation team is wholly independent
of The Planetary Society. The Planetary Society has no influence
over decisions made by the UnmannedSpaceflight.com moderators.

SUPPORT THE FORUM
Unmannedspaceflight.com is a project of the Planetary Society
and is funded by donations from visitors and members. Help keep
this forum up and running by contributing
here.